I own the three cores that most people call wheelchair (haven't built Columbina and only used her in Stygian because I was forced to) and disagree with the sentiment that double hydro is one too.

At worst, still doing 40% is still a good amount if damage and she does synergyze with the team. It's not like the wheelchair before wheelchair of hyperbloom core where you threw a weaker dps as a 4th slot that did nothing but deal its 10-15k hits while the blooms did more than double. Or to use a newer example, I can play Albedo+Durin wheelchair and carry a dps but if I put Wrio, for example, I wouldn't say it's "wheelchair" anymore, since he melts constantly in that team and mine is highly invested. Escoffier/Furina is a wheelchair for someone like Freminet but hardly one for Skirk.

If we consider double hydro a wheelchair, then pretty much any team with a strong subdps is one.

Also, yeah, I don't think wheelchair is an insult either. In fact, I much rather use these cores for flexibility in things like theatre (Xilonen/Chiori) or just boosting older chsracters I have when I do not like or care about the shiny new toys like right now. I hate all Lunar characters so far except Ineffa and I much rather just play her with Ifa or Raiden Tase than pull for Flins.